Polarized Photocathode R&D at BNL and spin consideration for the EIC
Authors:
- Jyoti BiswasJBJyoti Biswas
- Erdong WangEWErdong Wang
- Omer RahmanOROmer Rahman
- John SkaritkaJSJohn Skaritka
- Adam MastersAMAdam Masters
- Sylvain MarsillacSMSylvain Marsillac
- Tai-De LiTLTai-De Li
Open Access
- 7 February 2025
- conference paper
- Published by Sissa Medialab Srl
- Vol. 472, 026
Abstract
Superlattice GaAs photocathodes are vital for producing polarized electron beams for the Electron-Ion Collider (EIC) at Brookhaven National Laboratory. The electron pre-injector at the EIC requires a 7 nC bunch with at least 85% spin polarization from a GaAs-based superlattice cathode. The doping density of the very surface layer of the cathode needs to be optimized to extract a high bunch charge beam from the high-voltage DC gun. The polarization axis of the emitted beam is longitudinal, and it will be rotated to transverse direction using two Wien filters, each rotating the spin by 45 degrees. In this paper, we report our progress in recent R&D efforts for polarized photocathodes, and spin considerations for the EIC.Keywords
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